Automatic injection device for administration of high viscosity medication

ABSTRACT

An automatic injection device configured for injection of a material stored in a syringe into an injection site, the syringe including a generally cylindrical storage container and a piston disposed therewithin, whose exact initial axial position within the container is not predetermined, wherein axial forward displacement of the piston in the container forces the material forwardly out of the container, the automatic injection device including at least one spring drive assembly operative, when actuated, to initially apply a first axial force to the syringe, thereby to axially displace the syringe in a forward direction, and thereafter, responsive to driving engagement with the piston, to apply a second axial force, substantially greater than the first axial force, notwithstanding the fact that the exact axial position of the piston within the container is not predetermined, to the piston, thereby to axially forwardly displace the piston relative to the syringe.

REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.14/786,696 filed Oct. 23, 2015, which is a National Stage ofInternational Application No. PCT/IL2014/050375 filed Apr. 23, 2014,claiming priority based on U.S. Provisional Patent Application No.61/815,257, filed Apr. 23, 2013, the contents of all of which areincorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to automatic injection devices and moreparticularly to automatic injection devices for administration of highviscosity medications.

BACKGROUND OF THE INVENTION

The delivery of a high viscosity medication using a syringe typicallyrequires an automatic injector including a strong spring. One of thedisadvantages in the usage of such an automatic injector having a strongspring is that it can result in the breakage of the syringe during theoperation of the device. Additionally, dimensions of known automaticinjection devices having strong springs are normally substantiallylarger than those of injectors without such springs.

SUMMARY OF THE INVENTION

The present invention seeks to provide an improved automatic injectiondevice for high viscosity fluids.

There is thus provided in accordance with a preferred embodiment of thepresent invention an automatic injection device configured for injectionof a material stored in a syringe into an injection site, the syringeincluding a generally cylindrical storage container and a pistondisposed within the generally cylindrical storage container, whose exactinitial axial position within the generally cylindrical storagecontainer is not predetermined, wherein axial forward displacement ofthe piston in the generally cylindrical storage container forces thematerial forwardly out of the generally cylindrical storage container,the automatic injection device including at least one spring driveassembly operative, when actuated, to initially apply a first axialforce to the syringe, thereby to axially displace the syringe in aforward direction, and thereafter, responsive to driving engagement withthe piston, to apply a second axial force, substantially greater thanthe first axial force, notwithstanding the fact that the exact axialposition of the piston within the generally cylindrical storagecontainer is not predetermined, to the piston, thereby to axiallydisplace the piston relative to the syringe in the forward direction.

There is also provided in accordance with another preferred embodimentof the present invention an automatic injection device configured forinjection of a material stored in a syringe into an injection site, thesyringe including a generally cylindrical storage container and a pistondisposed within the generally cylindrical storage container, whose exactinitial axial position within the generally cylindrical storagecontainer is not predetermined, wherein axial forward displacement ofthe piston in the generally cylindrical storage container forces thematerial forwardly out of the generally cylindrical storage container,the automatic injection device including at least one spring driveassembly operative, when actuated, to initially apply a first axialforce to a plunger to axially displace the plunger in a forwarddirection, and thereafter, responsive to engagement of the plunger withthe piston, to apply a second axial force, substantially greater thanthe first axial force, notwithstanding the fact that the exact axialposition of the piston within the generally cylindrical storagecontainer is not predetermined, to the piston, thereby to axiallydisplace the piston relative to the syringe in the forward direction.

The is further provided in accordance with yet another preferredembodiment of the present invention an automatic injection deviceconfigured for injection of a material stored in a syringe into aninjection site, the syringe including a generally cylindrical storagecontainer and a piston disposed within the generally cylindrical storagecontainer, whose exact initial axial position within the generallycylindrical storage container is not predetermined, wherein axialforward displacement of the piston in the generally cylindrical storagecontainer forces the material forwardly out of the generally cylindricalstorage container, the automatic injection device including at least onespring drive assembly including at least one spring and at least oneselectably operable spring energy output force limiter, the at least oneselectably operable spring energy output force limiter beingautomatically disabled responsive to driving engagement of the at leastone spring drive assembly with the piston.

Preferably, the plunger is spaced from the piston when the automaticinjection device is in a storage orientation. Additionally oralternatively, the at least one spring drive assembly is configured toforwardly displace the plunger into engagement with the piston.

In accordance with a preferred embodiment of the present invention theat least one spring drive assembly includes at least one spring and atleast one selectably operable spring energy output force limiter, the atleast one selectably operable spring energy output force limiter beingautomatically disabled responsive to driving engagement of the at leastone spring drive assembly with the piston, the at least one springproviding the first axial force when the at least one selectablyoperable spring energy output force limiter is not disabled, andproviding the second axial force when the at least one selectablyoperable spring energy output force limiter is disabled. Additionally oralternatively, the at least one spring drive assembly stretches the atleast one selectably operable spring energy output force limiter.Alternatively or additionally, the at least one selectably operablespring energy output force limiter absorbs a portion of the force of theat least one spring drive assembly.

In accordance with a preferred embodiment of the present invention thesyringe includes a needle shield and the automatic injection device alsoincludes a needle shield remover, the needle shield remover including anexterior needle shield remover and an interior needle shield remover,the exterior needle shield remover and the interior needle shieldremover being configured to permit limited relative axial movementtherebetween, thereby to compensate for manufacturing toleranceinaccuracies of the automatic injection device and the syringe.Additionally, the exterior needle shield remover and the interior needleshield remover are configured to be axially displaceable relative toeach other at a first operative stage and not axially displaceablerelative to each other at a second operative stage.

Preferably, the automatic injection device also includes a syringesleeve and a relative movement restrictor operative to prevent relativemovement of the syringe and the syringe sleeve when the automaticinjection device is in a storage orientation. Preferably, the automaticinjection device and the syringe sleeve are configured to allow visualexamination of the contents of the syringe.

In accordance with a preferred embodiment of the present invention theautomatic injection device also includes a trigger button and a triggerbutton locking assembly operative to prevent forward movement of thetrigger button when the automatic injection device is in a storageorientation.

Preferably, the syringe also includes a needle and a needle shieldconfigured to prevent exposure of the needle in a post-injectionorientation.

In accordance with a preferred embodiment of the present invention theautomatic injection device also includes a front housing, a needleshield and a trigger button, the automatic injection device beingconfigured to be activatable by forwardly displacing the trigger buttonafter rearwardly displacing the needle shield relative to the fronthousing. Additionally, the automatic injection device is configured suchthat forward displacement of the trigger button actuates the at leastone spring drive assembly.

Preferably, the automatic injection device also includes a resilientring positioned on the syringe.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

FIG. 1 is a simplified pictorial exploded view illustration of anAutomatic Injection Device for Administration of High ViscosityMedication (AIDAHVM) constructive and operative in accordance with apreferred embodiment of the present invention;

FIGS. 2A and 2B are simplified rear facing pictorial view and side viewillustrations of an exterior Rigid Needle Shield (RNS) remover formingpart of the AIDAHVM of FIG. 1;

FIGS. 2C and 2D are simplified sectional view illustrations of theexterior RNS remover as shown in FIGS. 2A and 2B, taken along linesIIC-IIC and IID-IID in FIGS. 2A and 2C, respectively;

FIGS. 3A and 3B are a simplified side view illustration and a simplifiedtop view illustration of an interior Rigid Needle Shield (RNS) removerforming part of the AIDAHVM of FIG. 1;

FIG. 3C is a simplified sectional view illustration of the interior RNSremover as shown in FIGS. 3A and 3B, taken along lines IIIC-IIIC in FIG.3B;

FIG. 4A is a simplified pictorial view illustration of a front housingforming part of the AIDAHVM of FIG. 1;

FIGS. 4B and 4C are a simplified side view illustration and a simplifiedtop view illustration of the front housing as shown in FIG. 4A;

FIGS. 4D and 4E are simplified sectional view illustrations of the fronthousing as shown in FIGS. 4A-4C, taken along lines IVD-IVD and IVE-IVEin FIGS. 4B and 4C, respectively;

FIG. 5A is a simplified pictorial view illustration of a needle shieldforming part of the AIDAHVM of FIG. 1;

FIGS. 5B and 5C are a simplified top view illustration and a simplifiedside view illustration of the needle shield as shown in FIG. 5A;

FIG. 5D is a simplified sectional view illustration of the needle shieldas shown in FIGS. 5A-5C, taken along lines VD-VD in FIG. 5B;

FIG. 6A is a simplified pictorial view illustration of a fixed sleeveforming part of the AIDAHVM of FIG. 1;

FIGS. 6B and 6C are a simplified top view illustration and a simplifiedside view illustration of the fixed sleeve as shown in FIG. 6A;

FIG. 6D is a simplified sectional view illustration of the fixed sleeveas shown in FIGS. 6A-6C, taken along lines VID-VID in FIG. 6B;

FIGS. 7A and 7B are simplified pictorial view illustrations of a syringesleeve forming part of the AIDAHVM of FIG. 1;

FIGS. 7C and 7D are a simplified top view illustration and a simplifiedside view illustration of the syringe sleeve as shown in FIG. 7A;

FIG. 7E is a simplified sectional view illustration of the syringesleeve as shown in FIGS. 7A-7D, taken along lines VIIE-VIIE in FIG. 7C;

FIG. 8A is a simplified pictorial view illustration of a plunger rodforming part of the AIDAHVM of FIG. 1;

FIGS. 8B and 8C are a simplified top view illustration and a simplifiedside view illustration of the plunger rod as shown in FIG. 8A;

FIG. 8D is a simplified sectional view illustration of the plunger rodas shown in FIGS. 8A-8C, taken along lines VIIID-VIIID in FIG. 8B;

FIG. 9A is a simplified pictorial view illustration of a control unitforming part of the AIDAHVM of FIG. 1;

FIGS. 9B and 9C are a simplified side view illustration and a simplifiedtop view illustration of the control unit as shown in FIG. 9A;

FIGS. 9D and 9E are simplified sectional view illustrations of thecontrol unit as shown in FIGS. 9A-9C, taken along lines IXD-IXD andIXE-IXE, in FIGS. 9B and 9C, respectively;

FIG. 10A is a simplified pictorial view illustration of a rear housingforming part of the AIDAHVM of FIG. 1;

FIGS. 10B and 10C are a simplified side view illustration and asimplified top view illustration of the rear housing as shown in FIG.10A;

FIG. 10D is a simplified sectional view illustration of the rear housingas shown in FIGS. 10A-10C, taken along lines XD-XD in FIG. 10B;

FIG. 11A is a simplified pictorial view illustration of a ResilientDampening Element (RDE) forming part of the AIDAHVM of FIG. 1;

FIGS. 11B and 11C are a simplified side view illustration and asimplified top view illustration of the RDE as shown in FIG. 11A;

FIG. 12A is a simplified pictorial view illustration of a trigger buttonforming part of the AIDAHVM of FIG. 1;

FIGS. 12B and 12C are a simplified top view illustration and asimplified side view illustration of the trigger button as shown in FIG.12A;

FIGS. 12D and 12E are simplified sectional view illustrations of thetrigger button as shown in FIGS. 12A-12C, taken along lines XIID-XIIDand XIIE-XIIE, in FIGS. 12B and 12C, respectively;

FIG. 13A is a simplified pictorial view illustration of the AIDAHVM ofFIGS. 1-12D in a storage orientation;

FIG. 13B is a simplified, partially cut away, top view illustration ofthe AIDAHVM as shown in FIG. 13A;

FIGS. 13C and 13D are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 13A, taken along lines XIIIC-XIIIC andXIIID-XIIID, in FIGS. 13B and 13C, respectively;

FIG. 14A is a simplified pictorial view illustration of the AIDAHVM ofFIGS. 1-12D in a first operative orientation, following RNS removal;

FIGS. 14B and 14C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 14A, taken along lines XIVB-XIVB and XIVC-XIVC,in FIGS. 14A and 14B, respectively;

FIG. 15A is a simplified pictorial view illustration of the AIDAHVM ofFIGS. 1-12D in a second operative orientation, pushing against aninjection site;

FIGS. 15B and 15C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 15A, taken along lines XVB-XVB and XVC-XVC, inFIGS. 15A and 15B, respectively;

FIG. 16A is a simplified pictorial view illustration of the AIDAHVM ofFIGS. 1-12D in a third operative orientation, which is an activationorientation;

FIG. 16B is a simplified top view illustration of the AIDAHVM as shownin FIG. 16A;

FIGS. 16C and 16D are simplified sectional view illustrations of theAIDAHVM as shown in FIGS. 16A-16B, taken along lines XVIC-XVIC- andXVID-XVID, in FIGS. 16B and 16C, respectively;

FIG. 17A is a simplified pictorial view illustration of the AIDAHVM ofFIGS. 1-12D in a fourth operative orientation, including needlepenetration, start of injection, injection and end of injectionorientations;

FIGS. 17B and 17C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 17A in a needle penetration operativeorientation, taken along lines XVIIB-XVIIB and XVIIC-XVIIC, in FIGS. 17Aand 17B, respectively;

FIGS. 18A and 18B are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 17A in a start of injection operativeorientation, along the same lines as FIGS. 17B and 17C, respectively;

FIG. 19A is a simplified, partially cut away, front view illustration ofthe AIDAHVM as shown in FIG. 17A in an injection operative orientation;

FIGS. 19B and 19C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 19A, taken along lines XIXB-XIXB and XIXC-XIXC,in FIGS. 19A and 19B, respectively;

FIG. 20A is a simplified, partially cut away, front view illustration ofthe AIDAHVM as shown in FIG. 17A in an end of injection operativeorientation;

FIGS. 20B and 20C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 20A, taken along lines XXB-XXB and XXC-XXC, inFIGS. 20A and 20B, respectively;

FIG. 21A is a simplified pictorial view illustration of the AIDAHVM ofFIG. 1-12D in a discard orientation; and

FIGS. 21B and 21C are simplified sectional view illustrations of theAIDAHVM as shown in FIG. 21A, taken along lines XXIB-XXIB and XXIC-XXIC,in FIGS. 21A and 21B, respectively.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference is now made to FIG. 1, which is a simplified pictorialexploded view illustration of an Automatic Injection Device forAdministration of High Viscosity Medication (AIDAHVM) 100 constructiveand operative in accordance with a preferred embodiment of the inventionand to FIG. 13A, which is a simplified pictorial assembled view of theAIDAHVM of FIG. 1 in a storage orientation.

As seen in FIG. 1 and at least partially in FIG. 13A, AIDAHVM 100comprises an exterior Rigid Needle Shield (RNS) remover 200 at a forwardend, an interior RNS remover 202 and a front housing 300. Front housing300 is preferably adapted to engage exterior RNS remover 200.Preferably, when AIDAHVM 100 is assembled, exterior RNS remover 200partially surrounds interior RNS remover 202. Front housing 300 ispreferably formed of a transparent material. In order to visually shieldthe internal mechanism of AIDAHVM 100 from a user, an opaque label 301may cover the front housing 300.

AIDAHVM 100 also includes a needle shield 400, preferably configured tobe forwardly inserted and movable relative to front housing 300. Aneedle shield spring 402 is adapted to be inserted within needle shield400 to bias movement of needle shield 400 relative to front housing 300.A fixed sleeve 500 is configured to be inserted into needle shield 400and engage needle shield spring 402. A syringe sleeve 600, positionedrearward of fixed sleeve 500, is engaged therewith and movable relativethereto.

AIDAHVM 100 also includes a syringe 700, typically a conventionalsyringe including a generally cylindrical storage container containing amaterial to be injected, typically a medication. Syringe 700 preferablyincludes a Rigid Needle Shield (RNS) 702, typically a conventional RNS,a needle 707, preferably adhesively attached to a forward end of syringe700, and a piston 708, positioned within syringe 700 and generallydisposed at a rearward end of syringe 700. It is appreciated that theexact initial axial position of piston 708 within syringe 700 is notpredetermined. Syringe 700 defines a flange 704 at a rearward endthereof. A resilient ring 706 is preferably attached to syringe sleeve600.

Syringe 700 is preferably operatively inserted into syringe sleeve 600.A plunger rod 800 is configured to be operatively engaged with piston708 of syringe 700.

As seen further in FIG. 1, AIDAHVM also includes a control unit 900,operatively engaged with plunger rod 800, and at least one spring driveassembly. The at least one spring drive assembly includes an injectionspring 902, which is engaged at a forward end thereof with control unit900 and at a rearward end thereof with a rear housing 1000, and at leastone selectably operable spring energy output force limiter, such as aresilient dampening element (RDE) 1100, which is configured to belocated within rear housing 1000 in operative engagement with controlunit 900. AIDAHVM 100 includes a trigger button 1200 at a rearmostportion thereof.

Reference is now made to FIGS. 2A and 2B, which are simplified rearfacing pictorial view and side view illustrations of exterior RNS (RigidNeedle Shield) remover 200 forming part of AIDAHVM 100 of FIG. 1, and toFIGS. 2C and 2D, which are simplified sectional view illustrations ofexterior RNS remover 200 as shown in FIGS. 2A and 2B.

As seen in FIGS. 2A-2D, exterior RNS remover 200 is an integrally formedelement, preferably formed of plastic and arranged along a longitudinalaxis 204. Exterior RNS remover 200 preferably has a generally circularcylindrical configuration, including an outer cylindrical surface 206,an inner cylindrical surface 207, a forward end 208 and a rearward end210. Forward end 208 defines a circumferential ring 212. Outercylindrical surface 206 of exterior RNS remover 200 includes a taperedforward portion 214 and a generally cylindrical rearward portion 216.The diameter of tapered forward portion 214 adjacent generallycylindrical rearward portion 216 is greater than the diameter thereofadjacent circumferential ring 212.

A cylindrical wall portion 217 extends rearward from forward end 208 ofexterior RNS remover 200. Cylindrical wall portion 217 includes an outersurface 218 and an inner surface 220 which defines a cylindrical cavity221, including a forward cavity portion 222 and a rearward cavityportion 224 separated by an annular rearward facing flange 226. Theinner diameter of annular rearward facing flange 226 is less than thediameter of rearward cavity portion 224 and is also less than thediameter of forward cavity portion 222. The diameter of rearward cavityportion 224 and the diameter of forward cavity portion 222 are typicallyequal. A rearward end of rearward cavity portion 224 includes an annularrearward facing flange 264.

A rearward facing shoulder 234 is formed on inner cylindrical surface207, which divides an interior portion 228 of exterior RNS remover 200outside of cylindrical cavity 221 into a forward annular cavity 230,extending from front end 208 to rearward facing shoulder 234, and arearward annular portion 232, extending from rearward facing shoulder234 to rearward end 210. The diameter of forward annular cavity 230 isless than the diameter of rearward annular portion 232.

One or more, preferably two diametrically opposite, recessed portions235 are formed in inner cylindrical surface 207 between rearward facingshoulder 234 and rearward end 210. Recessed portion 235 is generallyrectangular and includes an outwardly tapered portion 237 adjacentrearward end 210. A generally rectangular axial protrusion 236 is formedon a portion of inner cylindrical surface 207 within recessed portion235.

Reference is now made to FIGS. 3A-3C, which are, respectively, asimplified side view illustration, a simplified top view illustrationand a simplified sectional view illustration of interior RNS (RigidNeedle Shield) remover 202, forming part of AIDAHVM 100 of FIG. 1.

As seen in FIGS. 3A-3C, interior RNS remover 202 is an integrally formedelement, preferably formed of plastic and arranged along longitudinalaxis 204. Interior RNS remover 202 preferably has a generallycylindrical configuration, including an outer surface 238 and an innersurface 240. Interior RNS remover 202 defines a forward end 242 and arearward end 244.

Forward end 242 of interior RNS remover 202 defines a circumferentialring 246, including a rearwardly facing inner wall 248. Outer surface238 includes a forward portion 250 adjacent circumferential ring 246 andextending rearwardly to a first forwardly facing shoulder 252. Outersurface 238 also includes an intermediate portion 254, extending fromfirst forwardly facing shoulder 252 to a second forwardly facingshoulder 256, and a rearward portion 258, extending from secondforwardly facing shoulder 256 to rearward end 244.

The diameter of the rearward portion 258 is greater than the diameter ofintermediate portion 254 and the diameter of intermediate portion 254 isgreater than the diameter of forward portion 250. The diameter ofcircumferential ring 246 is greater than the diameter of forward portion250.

Interior RNS remover 202 also includes one or more, preferably twodiametrically opposite, connectors 260 positioned on rearward portion258. Each connector 260 includes an inwardly radially extending arm 262,preferably a resilient radially extending arm.

Reference is now made to FIG. 4A, which is a simplified pictorial viewillustration of front housing 300 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 4B-4E, which are, respectively, a simplified top viewillustration, a simplified side view illustration, and first and secondsimplified sectional view illustrations, of front housing 300 as shownin FIG. 4A.

As seen in FIGS. 4A-4E, front housing 300 is an integrally formedelement having a generally cylindrical configuration, preferably formedof plastic and arranged along longitudinal axis 204.

As described hereinabove, front housing 300 is preferably formed of atransparent material to enable a user to see, inter alia, the operativeposition of AIDAHVM 100. As noted hereinabove, an opaque label 301 maybe provided to cover portions of front housing 300 to visually shieldthe internal mechanism of AIDAHVM 100 from a user. Alternatively, fronthousing 300 may be opaque and include a transparent window allowingvisual access to at least a body of syringe 700, to enable a user to seethe operative position of AIDAHVM 100.

Front housing 300 includes an outer housing surface 302, an innerhousing surface 304, a forward housing end 306 and a rearward housingend 308. Front housing 300, includes a relatively short forward portion310 and a relatively long rearward portion 312. A forwardly facingshoulder 318 is defined between relatively short forward portion 310 andrelatively long rearward portion 312. The diameter of relatively longrearward portion 312 is greater than the diameter of relatively shortforward portion 310.

Relatively long rearward portion 312 includes a forward end 320 adjacentforwardly facing shoulder 318.

At least one resilient arm 322 is positioned on relatively short forwardportion 310. Resilient arm 322 extends radially inwardly and, as seenparticularly in FIG. 4E, includes an internally extending protrusion324, having an inwardly tapered surface 326 and a forward facing edge328.

As seen particularly in FIG. 4E, at least one, and preferably twodiametrically opposite, elongate slots 330 are formed on inner housingsurface 304 of relatively long rearward portion 312 of front housing300. Elongate slots 330 are arranged parallel to longitudinal axis 204and extend rearwardly from forward end 320 along long rearward portion312.

Elongate slots 330 each define an internal T-shaped recess 332, whichincludes a forward inner cavity portion 334 and a rearward inner cavityportion 335. The width of rearward inner cavity portion 335 is greaterthan the width of forward inner cavity portion 334. Extending rearwardlyfrom forward end 320 are one or more, preferably two opposite facing,elongate elements 336 spaced from each other. Elongate elements 336partially cover forward inner cavity portion 334.

An aperture 342 is formed in front housing 300 at a rearward end ofrearward inner cavity portion 335.

One or more longitudinal ribs 338 are formed on inner housing surface304 of relatively long rearward portion 312 of front housing 300.Longitudinal ribs 338 are arranged parallel to longitudinal axis 204 andtypically extend rearwardly from forward end 320 along relatively longrearward portion 312. As seen in FIGS. 4D and 4E, longitudinal ribs 338preferably extend only partially along the length of relatively longrearward portion to rearward housing end 308.

Relatively long rearward portion 312 of front housing 300 alsopreferably includes one or more, preferably two diametrically opposite,forward apertures 340 extending longitudinally and arranged parallel toaxis 204. One or more, preferably two diametrically opposite, radiallyextending rearward apertures 341 are also formed on relatively longrearward portion 312 of front housing 300. Forward apertures 340 andrearward apertures 341 are mutually aligned along front housing 300parallel to longitudinal axis 204. One or more rearward apertures 344are also formed on relatively long rearward portion 312 of front housing300 and are disposed at a radial distance of generally 90° relative toforward apertures 340 and rearward apertures 341. As seen in FIG. 4E,apertures 342 and rearward apertures 344 are preferably mutually alignedparallel to longitudinal axis 204.

Reference is now made to FIG. 5A, which is a simplified pictorial viewillustration of needle shield 400 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 5B-5D, which are, respectively, a simplified top viewillustration, a simplified side view illustration and a simplifiedsectional view illustration of needle shield 400 as shown in FIG. 5A.

As seen in FIGS. 5A-5D, needle shield 400 is an integrally formedelement of a generally cylindrical shape, preferably formed of plasticand arranged along longitudinal axis 204, having an outer surface 404and an inner surface 406, and defining a forward end 408 and a rearwardend 410. Needle shield 400 preferably includes a forward portion 412 anda rearward portion 414. Preferably, the diameter of rearward portion 414is greater than the diameter of forward portion 412. Forward portion 412extends rearwardly from forward end 408 to a forward facing shoulder 416and rearward portion 414 extends rearwardly from forward facing shoulder416 to rearward end 410.

A radially extending circumferential ring 418 extends inwardly andrearwardly from forward end 408. Circumferential ring 418 defines arearward facing edge 419 adjacent inner surface 406 of needle shield400. An opening 420 extends rearwardly from circumferential ring 418 andis arranged parallel to longitudinal axis 204.

Needle shield 400 also includes one or more, preferably two, recessedportions 422 arranged rearwardly of rearward facing edge 419. One ormore, preferably two, longitudinal openings 424 extend rearwardly from apoint on forward portion 412 to rearward portion 414, each including arearward edge 425. Needle shield 400 also includes one or more,preferably two, longitudinal indication openings 426, each extendingrearwardly from a location rearward of recessed portion 422 on forwardportion 412 to rearward portion 414.

Needle shield 400 further includes one or more first apertures 428, eachlocated rearwardly of each of the one or more longitudinal openings 424.One or more second apertures 430 are also provided, each locatedrearwardly of each of the one or more indication openings 426.

In a most preferred embodiment, two longitudinal openings 424 areprovided and are aligned with two first apertures 428. In thisembodiment, longitudinal openings 424 are disposed at a radial distanceof generally 90° relative to two indication openings 426, each of whichare aligned with second apertures 430.

One or more longitudinal grooves 432 are formed on outer surface 404 ofthe rearward portion 414. Longitudinal grooves 432 extend rearwardlyfrom forward facing shoulder 416 and typically cover most of the lengthof rearward portion 414.

Extending rearwardly from rearward end 410 are one or more, preferablytwo, tabs 434, each defining an inner surface 435 and having an aperture436 therethrough. Tabs 434 are preferably positioned rearward oflongitudinal openings 424 and at a radial distance of generally 90°relative to recessed portions 422 and indication openings 426.

Reference is now made to FIG. 6A, which is a simplified pictorial viewillustration of fixed sleeve 500 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 6B-6D, which are, respectively, a simplified top viewillustration, a simplified side view illustration and a simplifiedsectional view illustration of fixed sleeve 500 as shown in FIG. 6A.

As seen in FIGS. 6A-6D, fixed sleeve 500 is an integrally formed elementhaving a generally cylindrical shape, preferably formed of plastic andarranged along longitudinal axis 204.

The fixed sleeve 500 includes an outer surface 502 and an inner surface504, and defines a forward end 506 and a rearward end 508. Fixed sleeve500 includes a forward cylindrical portion 510 and a rearwardcylindrical portion 512. The diameter of forward cylindrical portion 510is preferably greater than the diameter of rearward cylindrical portion512. Forward cylindrical portion 510 preferably extends rearwardly fromforward end 506 to a rearward facing shoulder 514 and rearwardcylindrical portion 512 extends rearwardly from rearward facing shoulder514 to rearward end 508. Forward cylindrical portion 510 defines aforward inner bore 516 and rearward cylindrical portion 512 defines arearward inner bore 518. The diameter of forward inner bore 516 isgreater than the diameter of rearward inner bore 518.

A circumferential ring 520 extends radially outwardly from forward end506 and preferably includes one or more, preferably two diametricallyopposite, radially extending protrusions 522.

Positioned rearwardly of each of radially extending protrusions 522 is aforwardly facing edge 523. A forward longitudinal rib 524 extendsrearwardly from each forwardly facing edge 523 to a rearwardly facingedge 515 positioned adjacent and forwardly of rearward facing shoulder514. Forward longitudinal ribs 524 include a top, generally planarportion, and a bottom portion, generally in the shape of a rectangularprism, including a generally wide forward portion 526 adjacent to theforwardly facing edge 523 and a generally narrow rearward portion 528adjacent the rearward facing shoulder 514. Generally narrow rearwardportion 528 of forward longitudinal rib 524 and top, generally planar,portion of forward longitudinal rib 524 define a gap therebetween.Extending outwardly from a rearward end of top, generally planar,portion of the forward longitudinal ribs 524 is a radial extension 530.

The provision of radial extension 530 and the gap between the top,generally planar, portion of forward longitudinal rib 524 and the narrowrearward portion 528 provide for a resilient characteristic of thelongitudinal ribs 524.

One or more rearward longitudinal ribs 532 extend forwardly fromrearward end 508 of fixed sleeve 500 to rearward facing shoulder 514.The rearward longitudinal ribs 532 are arranged parallel to longitudinalaxis 204 and aligned with the forward longitudinal ribs 524.

One or more longitudinal indication openings 536 extend forwardly froman edge 538 disposed adjacent to and forwardly of the rearward end 508of fixed sleeve 500 to an edge 540 disposed adjacent to and rearwardlyof forward end 506 of fixed sleeve 500.

One or more, preferably two, protrusions 542 are disposed at oppositeedges of each indication opening 536. Protrusions 542 extend radiallyoutwardly from forward cylindrical portion 510 of fixed sleeve 500.Protrusions 542 extend forwardly from rearward facing shoulder 514 alonga portion of the length of forward cylindrical portion 510 of fixedsleeve 500.

Reference is now made to FIGS. 7A and 7B, which are simplified pictorialview illustrations of syringe sleeve 600 forming part of AIDAHVM 100 ofFIG. 1, and to FIGS. 7C-7E, which are, respectively, a simplified topview illustration, a simplified side view illustration and a simplifiedsectional view illustration of syringe sleeve 600 as shown in FIGS. 7Aand 7B.

As seen in FIGS. 7A-7E, syringe sleeve 600 is an integrally formedelement having a generally cylindrical shape, preferably formed ofplastic and arranged along the longitudinal axis 204.

Syringe sleeve 600 includes an outer surface 602 and an inner surface604, and defines a forward end 606 and a rearward end 608. The syringesleeve 600 includes a cylindrical wall 609.

One or more, typically two, longitudinal openings 610 extend rearwardly,arranged parallel to longitudinal axis 204, from forward end 606partially through the length of cylindrical wall 609. Each longitudinalopening 610 defines a rearward edge 612 and two opposed lateral edges614.

One or more, preferably two, angular protrusions 616 are disposed onopposed lateral edges 614 of longitudinal opening 610. Angularprotrusions 616 include a straight edge 618, parallel to and radiallyextending outwardly from forward end 606 and an inclined edge 620,between the outward end of straight edge 618 and cylindrical wall 609.

Syringe sleeve 600 also includes one or more, typically two, forwardresilient arms 622, preferably disposed at a radial distance ofgenerally 90° relative to longitudinal openings 610 and arrangedparallel to longitudinal axis 204. Resilient arms 622 preferably includea forward extending portion 624, extending forwardly from rearward end608, a connecting portion 626, arranged perpendicularly to forwardextending portion 624, and a rearward facing portion 628, which extendsrearwardly from connecting portion 626 and is arranged parallel tolongitudinal axis 204. Rearward facing portion 628 terminates in aT-shape portion 630 on which is formed an extending protrusion 632.

Extending radially inwardly from rearward end 608 is a circumferentialring 634, which defines an inner forwardly facing surface 638 abuttinginner surface 604 of syringe sleeve 600. Cylindrical wall 609 andcircumferential ring 634 define a bore 636 extending longitudinallythrough syringe sleeve 600 and parallel to longitudinal axis 204.

One or more, preferably two diametrically opposite, rearward resilientarms 640 extend longitudinally rearwardly, arranged in the axialdirection of longitudinal axis 204 and at a radial distance of generally90° relative to forward resilient arms 622. Rearward resilient arms 640extend rearwardly from a point adjacent circumferential ring 634. Aradially inwardly extending protrusion 642 is formed at a rearward endof rearward resilient arm 640. Rearward resilient arms 640 include anouter surface 644, an inner surface 646 and a recess 648 formed on arearward portion of outer surface 644.

One or more, preferably two, guide grooves 650 extend longitudinally andare arranged parallel to longitudinal axis 204. Guide grooves 650 extendalong inner surface 604 from forward end 606 to the vicinity of rearwardend 608.

Reference is now made to FIG. 8A, which is a simplified pictorial viewillustration of plunger rod 800 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 8B-8D, which are, respectively, a simplified top viewillustration, a simplified side view illustration and a simplifiedsectional view illustration of plunger rod 800 as shown in FIG. 8A.

As seen in FIGS. 8A-8D, plunger rod 800 is an integrally formed element,preferably formed of plastic and arranged along longitudinal axis 204.Plunger rod 800 includes an outer surface 802 and has a forward end 804and a rearward end 806. Forward end 804 of plunger rod 800 includes aforwardly extending protrusion 808 formed thereon.

Extending rearwardly from rearward end 806 is a substantially hollowrear portion 810 defining a rearward edge 811. Extending rearwardly fromsubstantially hollow rear portion 810 are one or more, typically two,extension tabs 812. A recess 814 is formed in substantially hollow rearportion 810.

One or more, typically two, longitudinal guide ribs 816 are formed on anouter surface of substantially hollow rear portion 810. Longitudinalguide ribs 816 extend parallel to axis 204 along substantially hollowrear portion 810. Substantially hollow rear portion 810 also includesone or more, typically two, protrusions 818 formed thereon, preferablydisposed at a radial distance of generally 90° relative to longitudinalguide ribs 816. Preferably, protrusions 818 include a rearward facinginclined surface 820.

Reference is now made to FIG. 9A, which is a simplified pictorial viewillustration of control unit 900 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 9B-9E, which are, respectively, a simplified side viewillustration, a simplified top view illustration, and simplifiedsectional view illustrations of control unit 900 as shown in FIG. 9A.

As seen in FIGS. 9A-9E, control unit 900 is an integrally formedelement, preferably formed of plastic and arranged along thelongitudinal axis 204.

Control unit 900 includes a forward circumferential ring 903, connectedby one or more, preferably two, rearward extending arms 904 to arearward body portion 906. Forward circumferential ring 903 defines arearward ring end 908 and a forward ring end 910. Rearward extendingarms 904 define an inner surface 905 and an outer surface 907.

One or more, typically two, forward resilient arms 912 extend forwardlyfrom forward ring end 910 and are arranged parallel to longitudinal axis204. Forward resilient arms 912 define a forward end 914, an innersurface 916 and an outer surface 918. A longitudinal groove 913 extendsalong the entire length of rearward extending arm 904 and continuesalong the entire length of forward resilient arm 912.

Disposed within longitudinal groove 913, in the vicinity of forward end914, along an axis that is perpendicular to longitudinal axis 204, is aradially inwardly extending protrusion 920. Forward resilient arm 912also defines two edges 915 and 917 on opposite side of longitudinalgroove 913.

Edges 915 and 917 include lateral protrusions 922 adjacent forward end914 and extending rearwardly therefrom.

Extending radially outwardly from outer surface 918 of each of forwardresilient arms 912 is an external protrusion 924, disposed in vicinityof forward end 914.

Each of rearward extending arms 904 defines a rearward facing edge 926.Abutting rearward facing edges 926 are inwardly radially extendingrearward protrusions 928.

Rearward body portion 906 of control unit 900 includes one or more,preferably two diametrically opposite, forward facing portions 929, oneor more, preferably two diametrically opposite, intermediate portions932 and a generally annular end portion 934. Preferably, generallyannular end portion 934 includes two slightly elongate sections atlocations diametrically opposite one another and is connected, at aforward end thereof along the elongate sections, to intermediateportions 932, which are in turn connected, at a forward end, to forwardfacing portions 929.

Forward facing portions 929 preferably include a rearward portion 933and a forward portion 935, which preferably include a common inner wallsection. One or more recesses 937 are formed in an outer wall of forwardportion 935.

One or more, preferably two diametrically opposite, resilient arms 930extend forwardly from generally annular end portion 934, preferablyparallel to longitudinal axis 204 and forward resilient arms 912, at aradial distance of generally 90° relative to the elongate sections ofgenerally annular end portion 934.

Resilient arm 930 defines an outer surface 938 and an inner surface 940.An inwardly radially extending protrusion 942 extends from inner surface940 of resilient arm 930 near a forward end thereof. Forward of inwardlyradially extending protrusion 942, resilient arm 930 terminates in aninclined surface 936.

An intermediate outer surface 944 is defined between forward facingportion 929 and intermediate portion 932 on two opposite sides ofrearward body portion 906 that are orthogonal to the plane of connectingresilient arms 930. Preferably, extending radially outwardly fromgenerally annular end portion 934 are one or more, preferably four,rearward protrusions 946. Preferably, a pair of rearward protrusions 946are located on generally annular end portion 934 adjacent oppositelateral ends of each of resilient arms 930.

Preferably, extending radially outwardly from generally annular endportion 934 are also preferably formed a pair of spaced protrusions 948.Spaced protrusions 948 extend forwardly from generally annular endportion 934 to a rearward portion of intermediate outer surface 944 ofintermediate portions 932. Generally annular end portion 934 andintermediate portion 932 form an inclined surface 949 therebetween.Preferably, spaced protrusions 948 are disposed at a radial distance ofgenerally 90° relative to inwardly radially extending protrusions 942.

Each of forward facing portions 929 preferably defines a forward facingshoulder 950. Forward facing shoulders 950 are disposed slightlyforwardly of inwardly radially extending protrusions 942, and disposedat a radial distance of generally 90° relative to inwardly radiallyextending protrusions 942.

Reference is now made to FIG. 10A, which is a simplified pictorial viewillustration of rear housing 1000 forming part of AIDAHVM 100 of FIG. 1,and to FIGS. 10B-10D, which are, respectively, a simplified side viewillustration, a simplified top view illustration and a simplifiedsectional view illustration of rear housing 1000 as shown in FIG. 10A.

As seen in FIGS. 10A-10D, rear housing 1000 is an integrally formedelement, preferably formed of plastic and arranged along thelongitudinal axis 204.

Rear housing 1000 preferably includes an outer cylindrical portion 1002and an inner cylindrical portion 1004 connected by a circumferentialring 1006. Inner cylindrical portion 1004 defines an outer surface 1008,an inner surface 1010 and a forward end 1012. Circumferential ring 1006defines a forward facing annular edge surface 1014. The outercylindrical portion 1002 defines an outer surface 1016 and a rearwardend 1018.

Outer cylindrical portion 1002 rearwardly extends from forward facingannular edge surface 1014 to rearward end 1018. A circumferential ring1020 is formed rearward of and adjacent to rearward end 1018.

One or more, preferably two diametrically opposite, radially outwardlyextending protrusions 1022 are formed on outer surface 1016 of outercylindrical portion 1002. Protrusions 1022 are preferably arrangedperpendicular to longitudinal axis 204.

One or more, preferably two diametrically opposite, openings 1024 extendradially through outer cylindrical portion 1002, disposed at a radialdistance of generally 90° relative to protrusions 1022.

Inner cylindrical portion 1004 is substantially hollow, open at forwardend 1012 and partially closed at a rearward end by a circumferentialflange 1026, defining an inner forwardly facing surface 1028, an outerrearwardly facing edge 1029, and an opening 1027 extendinglongitudinally rearwardly from the outer rearwardly facing edge 1029.

One or more, preferably two diametrically opposite, resilient arms 1030are disposed in one or more, preferably two diametrically opposed,hollow portions of inner cylindrical portion 1004 rearward of forwardfacing annular edge surface 1014. Resilient arms 1030 extend forwardlyfrom the circumferential flange 1026 of the inner cylindrical portion1004.

Resilient arms 1030 include a T-shaped forward end 1032, defining twolateral extensions 1034 disposed therealong. One or more, preferablytwo, spaced radially outward protrusions 1038 are formed on an outersurface 1036 of resilient arms 1030 adjacent forward end 1032.

Reference is now made to FIG. 11A, which is a simplified pictorial viewillustration of Resilient Dampening Element (RDE) 1100 forming part ofAIDAHVM 100 of FIG. 1, and to FIGS. 11B-11C, which are, respectively, asimplified side view illustration and a simplified top view illustrationof RDE 1100 as shown in FIG. 11A.

As seen in FIGS. 11A-11C, RDE 1100 is an integrally formed elongateelement arranged along longitudinal axis 204. RDE 1100 is preferablyformed of thermoplastic material, such as polyethylene, or any othersuitable material that allows either plastic extension or elasticextension or both.

RDE 1100 preferably includes a forward holding portion 1102, anintermediate dampening portion 1104 and a rearward holding portion 1106,arranged longitudinally along longitudinal axis 204.

As seen in FIGS. 11A-11C, the cross-sectional area of intermediatedampening portion 1104 is substantially less than the cross-sectionalarea of both the forward holding portion 1102 and the rearward holdingportion 1106.

Forward holding portion 1102 of RDE 1100 defines a forward end 1108, andrearward holding portion 1106 defines a rearward end 1110. Forwardholding portion 1102 extends rearwardly from forward end 1108 to arearward facing edge 1112 and rearward holding portion 1106 defines aforward facing edge 1114.

Rearward holding portion 1106 and forward holding portion 1102 areconnected by intermediate dampening portion 1104, which is disposedlongitudinally between rearward facing edge 1112 of the forward holdingportion 1102 and the forward facing edge 1114 of the rearward holdingportion 1106.

Forward holding portion 1102 includes a forward broadened section 1116defining a rearward facing edge 1118, an intermediate section 1120,extending rearwardly therefrom, and an annular flange 1122, disposedrearwardly of intermediate section 1120. The cross-sectional area ofintermediate section 1120 is less than the cross-sectional area offorward broadened section 1116. Forward broadened section 1116 andannular flange 1122 are typically of equal cross-sectional area and arespaced apart by intermediate section 1120.

Formed on forward facing edge 1114 is a forward extending projection1124 arranged along longitudinal axis 204. Forward extending projection1124 defines a forward facing edge 1126. One or more, preferably twodiametrically opposite, protrusions 1128 are disposed on forward facingedge 1126. Protrusions 1128 preferably extend in a forward directionfrom forward facing edge 1126 and radially outwardly relative to axis204.

Reference is now made to FIG. 12A, which is a simplified pictorial viewillustration of trigger button 1200 forming part of AIDAHVM 100 of FIG.1, and to FIGS. 12B-12E, which are, respectively, a simplified top viewillustration, a simplified side view illustration and simplifiedsectional view illustrations of trigger button 1200 as shown in FIG.12A.

As seen in FIGS. 12A-12E, trigger button 1200 is an integrally formedelement, preferably formed of plastic and arranged along longitudinalaxis 204.

Trigger button 1200 has a generally cylindrical configuration anddefines an inner surface 1202, an outer surface 1204, an open forwardend 1206 and a closed rearward end 1208.

Extending radially outward from outer surface 1204 are one or morecircumferentially spaced projections 1210. Adjacent each of projections1210, an elongate longitudinal recess 1211 is typically formed in outersurface 1204.

Extending rearwardly from forward end 1206 are one or more, preferablytwo diametrically opposite, hollow generally rectangular recesses 1212.

One or more, preferably two, longitudinal resilient projections 1214extend forwardly from closed rearward end 1208. Longitudinal resilientprojections 1214 and generally rectangular recesses 1212 are alignedalong a mutual axis that is preferably perpendicular to longitudinalaxis 204.

Extending longitudinally forward from closed rearward end 1208 toforward end 1206 are one or more, preferably four circumferentiallyspaced, guide ribs 1216. Guide ribs 1216 are preferably arranged alongaxis 204 and parallel to the longitudinal resilient projections 1214.

Reference is now made to FIG. 13A, which is a simplified pictorial viewillustration of the AIDAHVM of FIG. 1 in a storage orientation, and toFIGS. 13B-13D, which are, respectively, a simplified top viewillustration and simplified sectional view illustrations of the AIDAHVMas shown in FIG. 13A.

As seen in FIGS. 13A-13D, AIDAHVM 100 is in a locked storageorientation, in which relative axial movement between the componentsthereof is prevented, except as described hereinbelow. In the lockedstorage orientation shown in FIGS. 13A-13D, needle 707 of syringe 700 iscovered by RNS 702.

As seen in FIGS. 13A-13D, fixed sleeve 500 is disposed within fronthousing 300 and is attached thereto by means of engagement of theforward longitudinal ribs 524 of the fixed sleeve 500 within elongateslots 330 of front housing 300. Forward longitudinal ribs 524 areinserted within the forward inner cavity portion 334 and are held withinby the elongate elements 336. Radial extensions 530 of the forwardlongitudinal ribs 524 are fixedly held within the apertures 342 of thefront housing 300 and limit rearward axial movement of the fixed sleeve500 relative to the front housing 300. The forwardly facing edge 523 ofthe forward longitudinal ribs 524 of the fixed sleeve 500 abuts theforward end 320 of the relatively long rearward portion 312 of the fronthousing and thus prevents forward axial movement of the fixed sleeve 500relative to the front housing 300.

In the storage orientation seen in FIGS. 13A-13D, spring 402 iscompressed and fixedly held between forward end 506 of the fixed sleeve500 at its rearward end and rearward facing edge 419 of needle shield400 at its forward end. Axial forward movement of needle shield 400relative to front housing 300 under the urging of spring 402 isprevented by the engagement of internally extending protrusion 324 ofthe resilient arms 322 of the front housing 300 with recessed portions422 of needle shield 400. The engagement of internally extendingprotrusion 324 with recessed portions 422 is achieved by the inwardlytapered surface 326 and the forward facing edge 328 forming a stop withrecessed portions 422 of needle shield 400. Resilient arms 322 of fronthousing 300 are supported at their outer surface by rectangular axialprotrusions 236 of exterior RNS remover 200.

The engagement of the resilient arms 322 of the front housing 300 withthe recessed portions 422 of the needle shield 400 in the storageorientation maintains the distance between the forward end 306 of thefront housing 300 and the forward end 408 of the needle shield 400, andthereby the length of the AIDHVM 100, at a minimum. The distance betweenthe forward end 306 of the front housing 300 and the forward end 408 ofthe needle shield 400, and thereby the length of the AIDHVM 100, isincreased only following the removal of the exterior RNS remover 200 andthe interior RNS remover 202, which disengages resilient arms 322 offront housing 300 from recessed portions 422 of needle shield 400, asdescribed further hereinbelow with reference to FIGS. 14A-14C.

Interior portion 228 of exterior RNS remover 200 surrounds relativelyshort forward portion 310 of front housing 300 and forward cavity 230 ofexterior RNS remover 200 partially surrounds the forward portion 412 ofthe needle shield 400. Cylindrical wall portion 217 is positioned withinthe opening 420 of needle shield 400. Interior RNS remover 202 ispositioned partially within the forward cavity portion 222 and partiallywithin the rearward cavity portion 224 of cylindrical cavity 221 ofexterior RNS remover 200.

Annular rearward facing flange 226 of exterior RNS remover 200 ismovably positioned along the length of the forward portion 250 betweenthe first forwardly facing shoulder 252 and the circumferential ring 246of the interior RNS remover 202. This relative arrangement between theannular rearward facing flange 226 of the exterior RNS remover 200 andthe forward portion 250 of the interior RNS remover 202 allows limitedaxial relative movement between the interior RNS remover 202 and theexterior RNS remover 200, along the length defined between thecircumferential ring 246 and the first forwardly facing shoulder 252, tocompensate for tolerance inaccuracies of AIDHVM 100 and syringe 700 thatmay result from the manufacturing process.

Interior RNS remover 202 fixedly holds RNS 702 within. RNS 702 is heldat a forward end by rearward facing inner wall 248. A rearward side ofRNS 702 is snap-fit into inwardly radially extending arms 262 ofconnectors 260 of interior RNS remover 202. Additionally, interior RNSremover 202 is partially inserted into the forward inner bore 516 of thefixed sleeve 500.

Syringe 700 is located within bore 636 of syringe sleeve 600 andrearward inner bore 518 of fixed sleeve 500. Syringe 700 is fixedly heldrelative to syringe sleeve 600 by situating flange 704 of syringe 700forward of radial protrusions 642 of rearward resilient arm 640 ofsyringe sleeve 600, between radial protrusions 642 and resilient ring706, attached to rearward end 608 of syringe sleeve 600.

The longitudinal opening 610 of the syringe sleeve 600 and thelongitudinal indication opening 536 of the fixed sleeve 500 arepositioned to allow visual examination of the contents of syringe 700through transparent portion of front housing 300. Needle 707 of thesyringe 700 is fixedly attached to the syringe 700, preferably by use ofan adhesive material.

Rearward longitudinal ribs 532 of the fixed sleeve 500 are inserted intoguide grooves 650 of the syringe sleeve 600, to ensure proper alignmentbetween the fixed sleeve 500 and the syringe sleeve 600. Engagement ofribs 532 and guide grooves 650 allows relative axial movement andprevents relative rotational movement between fixed sleeve 500 andsyringe sleeve 600.

Relative axial movement between syringe sleeve 600 and control unit 900is prevented by engagement of radially inwardly extending protrusions920 of forward resilient arms 912 of control unit 900 with recesses 648of rearward resilient arms 640 of syringe sleeve 600. Externalprotrusions 924 of forward resilient arms 912 engage inner surface 406of the needle shield 400 to prevent radially outward movement of forwardresilient arms 912.

Spring 902 is compressed and fixedly held between rearward ring end 908of the forward circumferential ring 903 of the control unit 900 at aforward end and by forward facing annular edge surface 1014 of the rearhousing 1000 at a rearward end thereof. Axial forward movement ofcontrol unit 900, under urging of spring 902 is prevented by engagementof spaced protrusions 948 of intermediate portion 932 of rearward bodyportion 906 of control unit 900 with lateral extensions 1034 of theresilient arms 1030 of the rear housing 1000. Spaced radially outwardprotrusions 1038 of resilient arms 1030 engage inner surface 435 ofneedle shield 400 to prevent radially outward movement of resilient arms1030.

Relative axial movement between rear housing 1000 and front housing 300is prevented by insertion of protrusions 1022 of the outer cylindricalportion 1002 of the rear housing 1000 into rearward apertures 341 offront housing 300.

RDE 1100 is inserted into the opening 1027 of the rear housing 1000.Forward axial movement of RDE 1100 relative to rear housing 1000 isprevented by engagement of forward facing edge 1114 of RDE 1100 withouter rearwardly facing edge 1029 of circumferential flange 1026 of rearhousing 1000. Rearward axial movement of RDE 1100 relative to rearhousing 1000 is prevented by engagement of protrusions 1128 of RDE 1100with inner forwardly facing surface 1028 of circumferential flange 1026of the rear housing 1000.

Rearward facing edge 1118 of forward broadened section 1116 of RDE 1100is disposed forwardly of inwardly radially extending protrusions 942 ofconnecting resilient arms 930 of control unit 900. Forward broadenedsection 1116 of RDE 1100 is located within recess 814 of plunger rod800.

Inclined surfaces 936 of connecting resilient arms 930 of the controlunit 900 are positioned against the rearward facing inclined surfaces820 of the diametrically opposite protrusions 818 of the plunger rod800. Forward axial movement of plunger rod 800 is prevented by inwardlyradially extending rearward protrusions 928 of the control unit 900 andrearward axial movement of plunger rod 800 is prevented by engagement ofrearward facing inclined surfaces 820 of plunger rod 800 with inclinedsurfaces 936 of resilient arms 930 of control unit 900.

As seen particularly in FIGS. 13C and 13D, in the storage orientation,forward end 804 of plunger rod 800 is inserted into syringe 700 and isrearwardly spaced from piston 708 of syringe 700.

Outer surface 1204 of trigger button 1200 is positioned between theouter cylindrical portion 1002 and the inner cylindrical portion 1004 ofthe rear housing 1000, while the circumferentially spaced projections1210 of the trigger button 1200 are disposed within openings 1024 of theouter cylindrical portion 1002 of the rear housing 1000. Rearward axialmovement of trigger button 1200 relative to rear housing 1000 isprevented by location of projections 1210 of trigger button 1200 withinopenings 1024 of rear housing 1000.

Longitudinal resilient projections 1214 of the trigger button 1200 aredisposed between forward facing portions 929 of rearward body portion906 of control unit 900 and between diametrically opposite resilientarms 1030 of rear housing 1000. Forward axial movement of trigger button1200 relative to rear housing 1000 is prevented by the location of theforward end of longitudinal resilient projections 1214 abutting inclinedsurface 949 of intermediate portion 932 of control unit 900.

It is appreciated that, if enabled, pressing the closed rearward end1208 of the trigger button 1200 forwardly would, as described furtherhereinbelow, force longitudinal resilient projections 1214 of triggerbutton 1200 to slide over inclined surface 949 of intermediate portion932 of control unit 900 and bend radially outwardly and thereby pushresilient arms 1030 of the rear housing 1000 radially outwardly relativeto the spaced protrusions 948 of control unit 900. However, in thestorage orientation seen in FIGS. 13A-13D, forward movement of triggerbutton 1200 is prevented by the location of inner surface 435 of needleshield 400 adjacent to and radially outwardly of spaced radially outwardprotrusions 1038 of the rear housing 1000 which prevents radiallyoutward movement of spaced radially outward protrusions 1038 of the rearhousing 1000.

Reference is now made to FIG. 14A, which is a simplified pictorial viewillustration of AIDAHVM 100 in a first operative orientation followingRNS removal and to FIGS. 14B-14C, which are simplified sectional viewillustrations of the AIDAHVM as shown in FIG. 14A.

As seen in FIGS. 14A-14C, RNS 702 has been removed by forward axialdisplacement of exterior RNS remover 200 and interior RNS remover 202relative to AIDAHVM 100, typically by a user pulling exterior RNSremover forwardly relative to front housing 300, thereby exposing needleshield 400 and needle 707.

In a first stage of the forward axial displacement of exterior RNSremover 200, exterior RNS remover 200 is forwardly axially displaceablerelative to both front housing 300 and to interior RNS remover 202. Thefirst stage continues until annular rearward facing flange 226 ofexterior RNS remover 200 engages circumferential ring 246 of interiorRNS remover 202.

In a second stage of the forward axial displacement of exterior RNSremover 200, exterior RNS remover 200 is forwardly axially displaceablerelative to front housing 300 but is not forwardly axially displaceablerelative to interior RNS remover 202. The second stage begins with theengagement of annular rearward facing flange 226 of exterior RNS remover200 with circumferential ring 246 of interior RNS remover 202. Duringthe second stage, exterior RNS remover 200 and interior RNS remover 202are forwardly axially displaced together relative to front housing 300.During the second stage, engagement of RNS 702 by inwardly radiallyextending arms 262 of connectors 260 of interior RNS remover 202 alsoforwardly axially displaces RNS 702, thereby removing RNS 702 fromsyringe 700.

Following the removal of the exterior RNS remover 200, rectangular axialprotrusions 236 of the exterior RNS remover 200 no longer supportresilient arms 322 of the front housing 300. This allows for theinwardly tapered surface 326 of resilient arms 322 of front housing 300are thereby free to slide over inclined surface of recessed portions 422of needle shield 400 and thereby radially outwardly open, allowingforward movement of needle shield 400 under the urging of spring 402.

Under the urging of spring 402, needle shield 400 proceeds forwardlyrelative to front housing 300 until rearward edges 425 of longitudinalopenings 424 of needle shield 400 engage extending protrusions 632 offorward resilient arms 622 of syringe sleeve 600.

As seen in FIGS. 14A-14C, in the first operative orientation, spacedradially outward protrusions 1038 of diametrically opposite resilientarms 1030 of rear housing 1000 are still radially supported by innersurface 435 of tabs 434 of needle shield 400.

Reference is now made to FIG. 15A, which is a simplified pictorial viewillustration of AIDAHVM 100 in a second operative orientation, pushingagainst an injection site and to FIGS. 15B and 15C, which are simplifiedsectional view illustrations of AIDAHVM 100 as shown in FIG. 15A.

Following the removal of the RNS 702 from the AIDAHVM 100, needle shield400 is axially rearwardly displaced relative to front housing 300,typically by the user pushing AIDAHVM 100 forwardly against an injectionsite. The axial rearward movement of needle shield 400 compresses spring402 until rearward end 410 of needle shield 400 abuts forward facingannular edge surface 1014 of rear housing 1000. Axial rearward movementof needle shield 400 causes internally extending protrusions 324 of arms322 of front housing 300 to slide into recessed portions 422 of theneedle shield 400. Further axial rearward movement of needle shieldrelative to front housing 300 causes internally extending protrusions324 of arms 322 to slide out of recessed portions 422 of needle shield400 and to be pushed radially outwardly by outer surface of forwardportion 412 of needle shield 400.

Following the rearward movement of the needle shield 400, the apertures436 of the tabs 434 of the needle shield 400 are positioned in front ofspaced radially outward protrusions 1038 of rear housing 1000 and infront of the rearward apertures 344 of front housing 300. In thisorientation, spaced radially outward protrusions 1038 are no longersupported by inner surface 435 of tabs 434 of the needle shield 400.

Reference is now made to FIG. 16A, which is a simplified pictorial viewillustration of AIDAHVM 100 in a third operative orientation, which isan activation orientation, and to FIGS. 16B-16D which are, respectively,a simplified top view illustration and simplified sectional viewillustrations of AIDAHVM 100 as shown in FIG. 16A.

As seen in FIGS. 16A-16D, following rearward displacement of needleshield 400, AIDAHVM 100 is activated by forwardly displacing triggerbutton, typically by a user pushing closed rearward end 1208 of triggerbutton 1200. Forward displacement of trigger button 1200 causeslongitudinal resilient projections 1214 of trigger button 1200 to slideover inclined surface 949 of control unit 900 and radially outwardly,thereby pushing resilient arms 1030 of rear housing 1000 radiallyoutwardly. As described hereinabove with reference to FIGS. 15A-15C,spaced radially outward protrusions 1038 of resilient arms 1030 of rearhousing 1000 are no longer supported by inner surface 435 of tabs 434 ofneedle shield 400, which frees trigger button 1200 to be moved axiallyforwardly. As described above, this allows longitudinal resilientprojections 1214 of trigger button 1200 together with resilient arms1030 of rear housing 1000 to bend radially outwardly. This forwardmovement also causes disengagement of lateral extensions 1034 ofdiametrically opposite resilient arms 1030 of rear housing 1000 fromspaced protrusions 948 of intermediate portion 932 of control unit 900,thus freeing the control unit 900 to move axially forwardly under theurging of spring 902.

Reference is now made to FIG. 17A, which is a simplified pictorial viewillustration of AIDAHVM 100 in a fourth operative orientation, whichincludes needle penetration, start of injection, injection and end ofinjection orientations, to FIGS. 17B and 17C, which are simplifiedsectional view illustrations of AIDAHVM 100 as shown in FIG. 17A in aneedle penetration operative orientation, FIGS. 18A and 18B, which aresimplified sectional view illustrations of AIDAHVM 100 as shown in FIG.17A in a start of injection operative orientation, FIGS. 19A-19C, whichare, respectively, a simplified, partially cut away, front viewillustration and simplified sectional view illustrations of AIDAHVM 100as shown in FIG. 17A in an injection operative orientation, and to FIGS.20A-20C, which are, respectively, a simplified, partially cut away,front view illustration and simplified sectional view illustrations ofAIDAHVM 100 as shown in FIG. 17A in an end of injection operativeorientation.

Referring now specifically to FIGS. 17A-17C, under the urging of spring902, control unit 900 moves axially forwardly and forwardly displacessyringe sleeve 600 together with syringe 700. Needle 707 passes throughopening 420 of needle shield 400 and penetrates the skin of the user,preferably achieving a desired penetration depth for administering themedication. Forward displacement of control unit 900 and syringe sleeve600 under urging of spring 902 continues until inner forwardly facingsurface 638 of syringe sleeve 600 abuts the rearward end 508 of thefixed sleeve 500. The forward displacement of control unit 900 positionsexternal protrusions 924 of forward resilient arms 912 of control unit900 within longitudinal indication openings 426 of needle shield 400 andforward apertures 340 of the front housing 300, thereby allowing forwardresilient arms 912 of control unit 900 to bend radially outwardly.

Forward displacement of control unit 900 also causes inwardly radiallyextending protrusions 942 of resilient arms 930 of control unit 900 toforwardly displace rearward facing edge 1118 of forward broadenedsection 1116 of the RDE 1100 forwardly, thereby stretching RDE 1100.

Intermediate dampening portion 1104, which is the weakest portion of RDE1100 is stretched at a force that is less than the axial force of spring902. Intermediate dampening portion 1104 thereby absorbs a portion ofthe axial force of spring 902 during its elongation and provides for thedampening of the movement of control unit 900.

It is appreciated that in the orientation shown in FIGS. 17A-17C,plunger rod 800 is not yet in engagement with piston 708 of syringe 700.

Referring now specifically to FIGS. 18A-18B, under the further urging ofspring 902, forward resilient arms 912 of the control unit 900 bendradially outwardly as control unit 900 is further displaced axiallyforwardly. The axial forward movement of control unit 900 causesradially inwardly extending protrusions 920 of forward resilient arms912 to slide out of recesses 648 and forwardly along the outer surface644 of rearward resilient arm 640 of syringe sleeve 600. The externalprotrusions 924 of the forward resilient arms 912 of the control unit900 are positioned below of the indication openings 426 of the needleshield 400 and forward apertures 340 of front housing 300.

As seen in FIGS. 18A and 18B, further forward movement of the controlunit 900 causes forward end 804 of plunger rod 800 to engage rearwardend of piston 708 of syringe 700.

Upon engagement on the plunger rod 800 and piston 708, the hydraulicresistance of the medication within syringe 700 while flowing throughneedle 707 slows the forward axial movement of plunger rod 800 duringfurther forward axial movement of control unit 900. Under the urging ofthe spring 902, the control unit 900 continues to move axially forwardrelative to plunger rod 800. Forward axial movement of control unit 900relative to plunger rod 800 continues until rearward edge 811 of plungerrod 800 reaches forward facing shoulders 950 of rearward body portion906 of control unit 900.

Forward axial movement of control unit 900 relative to plunger rod 800causes forward broadened section 1116 of RDE 1100 to enter into recess814 of substantially hollow rear portion 810 of plunger rod 800, thuspreventing radial movement of forward broadened section 1116 of RDE1100.

Forward axial movement of control unit 900 relative to plunger rod 800also causes protrusions 818 of plunger rod 800 to push against inclinedsurfaces 936 of resilient arms 930, thus outwardly radially bendingresilient arms 930 of control unit 900 and disengaging inwardly radiallyextending protrusions 942 of resilient arms 930 from rearward facingedge 1118 of RDE 1100, causing the application of the entire axial forceof spring 902 to the forward movement of the plunger rod 800 againstpiston 708 of syringe 700. Thus, responsive to driving engagement of theat least one spring drive assembly, including spring 902, with controlunit 900, plunger rod 800 and piston 708 the force limiting effect of atleast one selectably operable spring energy output force limiter, RDE1100, is automatically disabled.

Following further forward movement of control unit 900 under thecontinued urging of spring 902, longitudinal resilient projections 1214of trigger button 1200 are no longer supported by inclined surface 949of control unit 900 and bend radially inwardly to their originalposition together with resilient arms 1030 of rear housing 1000.

As seen in FIGS. 18A and 18B, spaced radially outward protrusions 1038of resilient arms 1030 of rear housing 1000 are positioned neitherwithin apertures 436 of tabs 434 of needle shield 400 nor withinrearward apertures 344 of front housing 300.

The dampening of the axial force of spring 902 by means of RDE 1100substantially decreases the axial force that is applied to syringe 700,and thereby reduces the probability of breakage of the syringe 700. Thedampening also reduces the noise created at the end of the syringe 700movement and at the engagement of the plunger rod 800 with piston 708 ofthe syringe 700.

The resilient ring 706 positioned on flange 704 of syringe 700 providesfor even stress distribution over flange 704 of syringe 700, thus alsoreducing the probability of breakage of the syringe 700 and alsodecreasing the noise level.

It is appreciated that the axial force of the spring 902 and thecross-sectional area of RDE 1100 may be selected based on the medicationbeing administered and the hydraulic force created thereby, thusproviding a range of injector forces without compromising the forcesapplied during injection.

Referring now specifically to FIGS. 19A-19C, further forward axialmovement of control unit 900, under urging of spring 902, producesforward axial movement of plunger rod 800 and piston 708 of syringe 700.Forward axial movement of control unit 900, plunger rod 800 and piston708 continues as the medication in syringe 700 is injected forwardlyinto the injection site. As the forward movement continues lateralprotrusions 922 of forward resilient arms 912 of control unit 900 bendradially outwardly above inclined edge 620 of the syringe sleeve 600 andfurther slide over protrusions 542 of forward cylindrical portion 510 offixed sleeve 500.

Referring now specifically to FIGS. 20A-20C, following the completion ofthe injection piston 708 of syringe 700 is disposed at the forward endof syringe 700 and forward resilient arms 912 of the control unit 900create an audible signal that indicates end of injection as lateralprotrusions 922 of the forward resilient arms 912 of the control unit900 disengage from protrusions 542 of forward cylindrical portion 510 offixed sleeve 500.

Reference is now made to FIG. 21A, which is a simplified pictorial viewillustration of AIDAHVM 100 in a discard orientation, and to FIGS.21B-21C which are simplified sectional view illustrations of AIDAHVM 100as shown in FIG. 21A.

Following the end of the injection of the medication in syringe 700, theuser removes AIDAHVM 100 from the injection site. As the AIDAHVM 100 isremoved, needle shield 400 moves axially forward relative to fronthousing 300 under the urging of spring 402 and covers needle 707 ofsyringe 700. The forward axial movement of needle shield 400 relative tofront housing 300 continues until rearward edge 425 of longitudinalopenings 424 of needle shield 400 engages extending protrusions 632 offorward resilient arms 622 of syringe sleeve 600.

As seen in FIGS. 21A-21C, internally extending protrusions 324 ofresilient arms 322 of the front housing 300 slide into longitudinalindication opening 426 of the needle shield 400 adjacent its forwardedge, as resilient arms 322 of front housing 300 returns to theiroriginal position.

In the discard orientation shown in FIGS. 21A-21C, needle 707 of syringe700 is shielded by needle shield 400. Attempted retraction of needleshield 400 into front housing 300 by rearward axial displacement ofneedle shield 400 relative to front housing 300 is prevented, therebypreventing exposure of needle 707 of syringe 700, by location of forwardedge of longitudinal indication opening 426 of needle shield 400 forwardof forward facing edge 328 of the resilient arms 322 of the fronthousing 300.

It is appreciated that the term “at a radial distance of generally 90°”as used throughout the description of the present invention refers to aradial distance of 90°±5°.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed hereinabove. Rather the scope of the present inventionincludes both combinations and sub-combinations of various featuresdescribed hereinabove as well as variations and modifications thereofwhich are not in the prior art.

1. An automatic injection device configured for injection of a material stored in a syringe into an injection site, said syringe including a generally cylindrical storage container and a piston disposed within said generally cylindrical storage container, wherein axial forward displacement of said piston in said generally cylindrical storage container forces said material forwardly out of said generally cylindrical storage container, said automatic injection device comprising: a needle shield; a trigger button, at least one spring drive assembly including: at least one spring; and at least one selectably operable spring energy output force limiter, configured to be operative prior to axial forward displacement of said piston relative to said syringe, wherein said automatic injection device being configured to be activatable by displacing said trigger button following displacement of said needle shield.
 2. An automatic injection device according to claim 1 and wherein said at least one spring drive assembly operative, when actuated: to initially apply a first axial force to a plunger to axially displace said plunger in a forward direction; and thereafter, responsive to engagement of said plunger with said piston, to apply a second axial force, greater than said first axial force, to said piston, thereby to axially displace said piston relative to said syringe in said forward direction.
 3. An automatic injection device according to claim 1 and wherein said at least one spring drive assembly operative, when actuated: to initially apply a first axial force to said syringe, thereby to axially displace said syringe in a forward direction; and thereafter, responsive to driving engagement with said piston, to apply a second axial force, greater than said first axial force, to said piston, thereby to axially displace said piston relative to said syringe in said forward direction.
 4. An automatic injection device according to claim 1 and wherein said at least one selectably operable spring energy output force limiter being automatically disabled responsive to driving engagement of said at least one spring drive assembly with said piston.
 5. An automatic injection device according to claim 1 and wherein said at least one spring drive assembly comprises: said at least one spring providing a first axial force when said at least one selectably operable spring energy output force limiter is not disabled, and providing a second axial force, greater than said first axial force, when said at least one selectably operable spring energy output force limiter is disabled.
 6. An automatic injection device according to claim 1 and wherein said selectably operable spring energy output force limiter is stretchable.
 7. An automatic injection device according to claim 1 and wherein said at least one selectably operable spring energy output force limiter absorbs a portion of the force of said at least one spring.
 8. An automatic injection device according to claim 1 and wherein said syringe comprises a cap mounted onto said needle and said automatic injection device also comprises a cap remover, said cap remover including: an exterior cap remover; and an interior cap remover, said exterior cap remover and said interior cap remover being configured to permit limited relative axial movement therebetween, thereby to compensate for manufacturing tolerance inaccuracies of said automatic injection device and said syringe.
 9. An automatic injection device according to claim 1 and also comprising a syringe sleeve and a relative movement restrictor operative to prevent relative movement of said syringe and said syringe sleeve when said automatic injection device is in a storage orientation.
 10. An automatic injection device according to claim 1 and also comprising a trigger button locking assembly operative to prevent movement of said trigger button when said automatic injection device is in a storage orientation.
 11. An automatic injection device according to claim 1 and wherein said needle shield is configured to prevent exposure of said needle in a post-injection orientation.
 12. An automatic injection device according to claim 1 and also comprising a front housing and wherein said automatic injection device being configured to be activatable by forwardly displacing said trigger button after rearwardly displacing said needle shield relative to said front housing.
 13. An automatic injection device according to claim 1 and wherein said automatic injection device is configured such that displacement of said trigger button actuates said at least one spring drive assembly.
 14. An automatic injection device according to claim 1 and also comprising a resilient ring positioned on said syringe.
 15. An automatic injection device configured for injection of a material stored in a syringe into an injection site, said syringe including a generally cylindrical storage container and a piston disposed within said generally cylindrical storage container, wherein axial forward displacement of said piston in said generally cylindrical storage container forces said material forwardly out of said generally cylindrical storage container, said automatic injection device comprising: at least one spring drive assembly including: at least one spring; at least one selectably operable spring energy output force limiter, configured to be operative prior to axial forward displacement of said piston relative to said syringe; and a sleeve configured to produce an audible signal that indicates end of injection following axial forward displacement of said piston.
 16. An automatic injection device according to claim 15 and wherein said automatic injection device also comprising a needle shield and a trigger button, wherein said automatic injection device being configured to be activatable by displacing said trigger button following displacement of said needle shield.
 17. An automatic injection device according to claim 15 and wherein said at least one spring drive assembly comprises: said at least one spring providing a first axial force when said at least one selectably operable spring energy output force limiter is not disabled, and providing a second axial force, greater than said first axial force, when said at least one selectably operable spring energy output force limiter is disabled.
 18. An automatic injection device according to claim 15 and wherein said at least one selectably operable spring energy output force limiter being automatically disabled responsive to driving engagement of said at least one spring drive assembly with said piston.
 19. An automatic injection device according to claim 15 and wherein said selectably operable spring energy output force limiter is stretchable.
 20. An automatic injection device according to claim 15 and wherein said at least one selectably operable spring energy output force limiter absorbs a portion of the force of said at least one spring. 